Friday, November 21, 2008

Friday Fault Photos #8

While out climbing around in the hills the other day, with MOH on one of our hikes, I came upon a fault zone in quartzite, along with a lot of steep and precarious ledges. There I am, above, standing on one ledge, looking down to another ledge in the shadows below the pine tree on the left, and looking even farther down to the ground below. Why am I doing that?
I'm doing that because from the ledge below the pine tree, and all the way to the ground, the entire mini-cliff of quartzite is slickensided. In the photo above, I've reached the lower ledge, and am trying to get a foothold so I can take a photo (surprise!). You can see some of the slickensides just above that field boot of mine.
Ah! Here I've finally reached the point I want, and am standing on the ledge, looking down at a golden brown, iron-stained, slickensided surface, with my boots pointing more or less parallel to the slickenlines (straight down). It's a funny perspective, and MOH tells me that when I climbed down the ledge to the ground, that the slickensided mini-cliff was over my head, which means it was at least 5 feet high, maybe higher.

6 comments:

Unknown said...

I think slickensides are awe-inspiring. They are a such a physically small indicator of a vast and powerful process... plus they match my corduroy pants.

Cool footholds! :) I think you can claim the first ascent (FA) of that boulder. That means you get to name it...!

Andrew Alden, Oakland Geology blog said...

Gee, wouldn't it be safer just to point the camera UP from the ground?

GeologyJoe said...

slicks are always a cool feature to find.

Silver Fox said...

Hmmm... not sure what I would name a small portion of a huge outcrop, maybe Jill or Bob or... I think MOH had gone up that way before I did, anyway, so he gets FA.

Yeah, Andrew, I thought about going down and taking the pictures, but there I was... And there were trees to hold on to. Trees can be good friends.

Slicks are great. They are everywhere. (Well, a lot of places, anyway - here in the west where we have lots of outcrops and lots of active and old faults lying around here and there.)

Anonymous said...

Re: slickensides. I was out in a boat visiting the Blue Grotto on Malta when I looked up and almost upset the boat by pointing and shouting 'slickensides' - and not just slickensides - a lovely fault breccia too. All the non-geos in the boat were a bit shattered and bemused.

Silver Fox said...

Dear Anon, nice use of the word "shattered."